This is a classic example of anthropic reasoning. The idea is that some finetuning took place in order to make life on earth possible. Of course, in reality the reverse it true: life arises only there where it is possible for it to arise. If the earth had been too close to the sun, or too far away from it for life to arise, then life would obviously not have arisen on earth and we would not be having this conversation.
Ask yourself this question: why is it that Mercurians, Venutians, Martians, Jovians, Saturnians, Uranians, Neptunians and Plutonians, all of them, without exception, do not wonder why the circumstances regarding their planet - its atmosphere, its orbit, etc - are so miraculously finetuned as to allow their own existence? The reason none of these races wonder about it is that none of these races exist. This is because the circumstances are in fact NOT very suitable for the emergence of life on their respective planets.
Simplified, you can think of a solar system as a continuum of orbits where water either freezes, stays liquid, or boils and evaporates. Liquid water happens to be a necessary asset for life as we know it to exist. Therefore, the range of orbits where water stays liquid forms a life-friendly niche. There are probably billions of solar systems in the universe. So if some of them have a rocky planet in the range of orbits allowing liquid water, life could arise there. This is what happened in our solar system, and there really is nothing miraculous about it.
"Ignorance more frequently begets confidence than does knowledge: it is those who know little, not those who know much, who so positively assert that this or that problem will never be solved by science." - Charles Darwin.
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